# Proposed AD FAA-2021-0101: Bombardier, Inc., Airplanes

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 2021-09-17
- Products: Bombardier
- Product type: Aircraft
- Action: Notice of proposed rulemaking (NPRM).
- Published: February 26, 2021, 86 FR 11667
- Comments due: April 12, 2021
- Became: [AD 2021-09-17](https://openairdocs.org/ad/2021-09-17)
- Docket: FAA-2021-0101 (https://www.regulations.gov/docket/FAA-2021-0101, where comments are filed)
- Project: MCAI-2020-01084-T
- FR document: 2021-03745
- Official PDF: https://openairdocs.org/files/sha256/93/f5/93f5d2fa88fab0138e7b8010930ef64d7f41773b883c8269cdf1b410eb749d3e (from https://www.govinfo.gov/content/pkg/FR-2021-02-26/pdf/2021-03745.pdf)
- Federal Register: https://www.federalregister.gov/documents/2021/02/26/2021-03745/airworthiness-directives-bombardier-inc-airplanes
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/548B3A8211BDEFB3862586880068645A.0001
- Page: https://openairdocs.org/proposed/FAA-2021-0101

## Summary

The FAA proposes to adopt a new airworthiness directive (AD) for certain Bombardier, Inc., Model BD-100-1A10 airplanes. This proposed AD was prompted by a report that the inboard multi-function spoiler (MFS) surfaces failed to deploy, which was caused by missing notches on the piston seal of the MFS power control units (PCUs). This proposed AD would require an inspection to determine if affected MFS PCUs are installed, and replacement of affected MFS PCUs. The FAA is proposing this AD to address the unsafe condition on these products.

## Notices in this docket

- Feb 26, 2021: Notice of proposed rulemaking (NPRM). (first notice), FR document 2021-03745, comments due Apr 12, 2021 (https://www.federalregister.gov/documents/2021/02/26/2021-03745/airworthiness-directives-bombardier-inc-airplanes)

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